[PATCH AUTOSEL 4.9 1/6] ARM: 8977/1: ptrace: Fix mask for thumb breakpoint hook

[PATCH AUTOSEL 4.9 1/6] ARM: 8977/1: ptrace: Fix mask for thumb breakpoint hook

[Sasha Levin]

From: Fredrik Strupe <fredrik@strupe.net>

[ Upstream commit 3866f217aaa81bf7165c7f27362eee5d7919c496 ]

call_undef_hook() in traps.c applies the same instr_mask for both 16-bit
and 32-bit thumb instructions. If instr_mask then is only 16 bits wide
(0xffff as opposed to 0xffffffff), the first half-word of 32-bit thumb
instructions will be masked out. This makes the function match 32-bit
thumb instructions where the second half-word is equal to instr_val,
regardless of the first half-word.

The result in this case is that all undefined 32-bit thumb instructions
with the second half-word equal to 0xde01 (udf #1) work as breakpoints
and will raise a SIGTRAP instead of a SIGILL, instead of just the one
intended 16-bit instruction. An example of such an instruction is
0xeaa0de01, which is unallocated according to Arm ARM and should raise a
SIGILL, but instead raises a SIGTRAP.

This patch fixes the issue by setting all the bits in instr_mask, which
will still match the intended 16-bit thumb instruction (where the
upper half is always 0), but not any 32-bit thumb instructions.

Cc: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Fredrik Strupe <fredrik@strupe.net>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 arch/arm/kernel/ptrace.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/arm/kernel/ptrace.c b/arch/arm/kernel/ptrace.c
index ae738a6319f6..364985c96a92 100644
--- a/arch/arm/kernel/ptrace.c
+++ b/arch/arm/kernel/ptrace.c
@@ -227,8 +227,8 @@ static struct undef_hook arm_break_hook = {
 };
 
 static struct undef_hook thumb_break_hook = {
-	.instr_mask	= 0xffff,
-	.instr_val	= 0xde01,
+	.instr_mask	= 0xffffffff,
+	.instr_val	= 0x0000de01,
 	.cpsr_mask	= PSR_T_BIT,
 	.cpsr_val	= PSR_T_BIT,
 	.fn		= break_trap,
-- 
2.25.1

[PATCH AUTOSEL 4.9 1/6] ARM: 8977/1: ptrace: Fix mask for thumb breakpoint hook

[Sasha Levin]

From: Fredrik Strupe <fredrik@strupe.net>

[ Upstream commit 3866f217aaa81bf7165c7f27362eee5d7919c496 ]

call_undef_hook() in traps.c applies the same instr_mask for both 16-bit
and 32-bit thumb instructions. If instr_mask then is only 16 bits wide
(0xffff as opposed to 0xffffffff), the first half-word of 32-bit thumb
instructions will be masked out. This makes the function match 32-bit
thumb instructions where the second half-word is equal to instr_val,
regardless of the first half-word.

The result in this case is that all undefined 32-bit thumb instructions
with the second half-word equal to 0xde01 (udf #1) work as breakpoints
and will raise a SIGTRAP instead of a SIGILL, instead of just the one
intended 16-bit instruction. An example of such an instruction is
0xeaa0de01, which is unallocated according to Arm ARM and should raise a
SIGILL, but instead raises a SIGTRAP.

This patch fixes the issue by setting all the bits in instr_mask, which
will still match the intended 16-bit thumb instruction (where the
upper half is always 0), but not any 32-bit thumb instructions.

Cc: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Fredrik Strupe <fredrik@strupe.net>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 arch/arm/kernel/ptrace.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/arm/kernel/ptrace.c b/arch/arm/kernel/ptrace.c
index ae738a6319f6..364985c96a92 100644
--- a/arch/arm/kernel/ptrace.c
+++ b/arch/arm/kernel/ptrace.c
@@ -227,8 +227,8 @@ static struct undef_hook arm_break_hook = {
 };
 
 static struct undef_hook thumb_break_hook = {
-	.instr_mask	= 0xffff,
-	.instr_val	= 0xde01,
+	.instr_mask	= 0xffffffff,
+	.instr_val	= 0x0000de01,
 	.cpsr_mask	= PSR_T_BIT,
 	.cpsr_val	= PSR_T_BIT,
 	.fn		= break_trap,
-- 
2.25.1


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[PATCH AUTOSEL 4.9 2/6] sched/fair: Don't NUMA balance for kthreads

[Sasha Levin]

From: Jens Axboe <axboe@kernel.dk>

[ Upstream commit 18f855e574d9799a0e7489f8ae6fd8447d0dd74a ]

Stefano reported a crash with using SQPOLL with io_uring:

  BUG: kernel NULL pointer dereference, address: 00000000000003b0
  CPU: 2 PID: 1307 Comm: io_uring-sq Not tainted 5.7.0-rc7 #11
  RIP: 0010:task_numa_work+0x4f/0x2c0
  Call Trace:
   task_work_run+0x68/0xa0
   io_sq_thread+0x252/0x3d0
   kthread+0xf9/0x130
   ret_from_fork+0x35/0x40

which is task_numa_work() oopsing on current->mm being NULL.

The task work is queued by task_tick_numa(), which checks if current->mm is
NULL at the time of the call. But this state isn't necessarily persistent,
if the kthread is using use_mm() to temporarily adopt the mm of a task.

Change the task_tick_numa() check to exclude kernel threads in general,
as it doesn't make sense to attempt ot balance for kthreads anyway.

Reported-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/865de121-8190-5d30-ece5-3b097dc74431@kernel.dk
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 kernel/sched/fair.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 5e65c7eea872..8233032a2f01 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -2542,7 +2542,7 @@ void task_tick_numa(struct rq *rq, struct task_struct *curr)
 	/*
 	 * We don't care about NUMA placement if we don't have memory.
 	 */
-	if (!curr->mm || (curr->flags & PF_EXITING) || work->next != work)
+	if ((curr->flags & (PF_EXITING | PF_KTHREAD)) || work->next != work)
 		return;
 
 	/*
-- 
2.25.1

[PATCH AUTOSEL 4.9 3/6] net: usb: qmi_wwan: add Telit LE910C1-EUX composition

[Sasha Levin]

From: Daniele Palmas <dnlplm@gmail.com>

[ Upstream commit 591612aa578cd7148b7b9d74869ef40118978389 ]

Add support for Telit LE910C1-EUX composition

0x1031: tty, tty, tty, rmnet
Signed-off-by: Daniele Palmas <dnlplm@gmail.com>
Acked-by: Bjørn Mork <bjorn@mork.no>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/net/usb/qmi_wwan.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/net/usb/qmi_wwan.c b/drivers/net/usb/qmi_wwan.c
index 5755eec00d7f..9a873616dd27 100644
--- a/drivers/net/usb/qmi_wwan.c
+++ b/drivers/net/usb/qmi_wwan.c
@@ -921,6 +921,7 @@ static const struct usb_device_id products[] = {
 	{QMI_FIXED_INTF(0x1bbb, 0x0203, 2)},	/* Alcatel L800MA */
 	{QMI_FIXED_INTF(0x2357, 0x0201, 4)},	/* TP-LINK HSUPA Modem MA180 */
 	{QMI_FIXED_INTF(0x2357, 0x9000, 4)},	/* TP-LINK MA260 */
+	{QMI_QUIRK_SET_DTR(0x1bc7, 0x1031, 3)}, /* Telit LE910C1-EUX */
 	{QMI_QUIRK_SET_DTR(0x1bc7, 0x1040, 2)},	/* Telit LE922A */
 	{QMI_FIXED_INTF(0x1bc7, 0x1100, 3)},	/* Telit ME910 */
 	{QMI_FIXED_INTF(0x1bc7, 0x1101, 3)},	/* Telit ME910 dual modem */
-- 
2.25.1

[PATCH AUTOSEL 4.9 4/6] NFC: st21nfca: add missed kfree_skb() in an error path

[Sasha Levin]

From: Chuhong Yuan <hslester96@gmail.com>

[ Upstream commit 3decabdc714ca56c944f4669b4cdec5c2c1cea23 ]

st21nfca_tm_send_atr_res() misses to call kfree_skb() in an error path.
Add the missed function call to fix it.

Fixes: 1892bf844ea0 ("NFC: st21nfca: Adding P2P support to st21nfca in Initiator & Target mode")
Signed-off-by: Chuhong Yuan <hslester96@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/nfc/st21nfca/dep.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/nfc/st21nfca/dep.c b/drivers/nfc/st21nfca/dep.c
index 798a32bbac5d..e023a679bdea 100644
--- a/drivers/nfc/st21nfca/dep.c
+++ b/drivers/nfc/st21nfca/dep.c
@@ -184,8 +184,10 @@ static int st21nfca_tm_send_atr_res(struct nfc_hci_dev *hdev,
 		memcpy(atr_res->gbi, atr_req->gbi, gb_len);
 		r = nfc_set_remote_general_bytes(hdev->ndev, atr_res->gbi,
 						  gb_len);
-		if (r < 0)
+		if (r < 0) {
+			kfree_skb(skb);
 			return r;
+		}
 	}
 
 	info->dep_info.curr_nfc_dep_pni = 0;
-- 
2.25.1

[PATCH AUTOSEL 4.9 5/6] drivers/net/ibmvnic: Update VNIC protocol version reporting

[Sasha Levin]

From: Thomas Falcon <tlfalcon@linux.ibm.com>

[ Upstream commit 784688993ebac34dffe44a9f2fabbe126ebfd4db ]

VNIC protocol version is reported in big-endian format, but it
is not byteswapped before logging. Fix that, and remove version
comparison as only one protocol version exists at this time.

Signed-off-by: Thomas Falcon <tlfalcon@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/net/ethernet/ibm/ibmvnic.c | 8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/drivers/net/ethernet/ibm/ibmvnic.c b/drivers/net/ethernet/ibm/ibmvnic.c
index 897a87ae8655..20f7ab4aa2f1 100644
--- a/drivers/net/ethernet/ibm/ibmvnic.c
+++ b/drivers/net/ethernet/ibm/ibmvnic.c
@@ -3362,12 +3362,10 @@ static void ibmvnic_handle_crq(union ibmvnic_crq *crq,
 			dev_err(dev, "Error %ld in VERSION_EXCHG_RSP\n", rc);
 			break;
 		}
-		dev_info(dev, "Partner protocol version is %d\n",
-			 crq->version_exchange_rsp.version);
-		if (be16_to_cpu(crq->version_exchange_rsp.version) <
-		    ibmvnic_version)
-			ibmvnic_version =
+		ibmvnic_version =
 			    be16_to_cpu(crq->version_exchange_rsp.version);
+		dev_info(dev, "Partner protocol version is %d\n",
+			 ibmvnic_version);
 		send_cap_queries(adapter);
 		break;
 	case QUERY_CAPABILITY_RSP:
-- 
2.25.1

[PATCH AUTOSEL 4.9 5/6] drivers/net/ibmvnic: Update VNIC protocol version reporting

[Sasha Levin]

From: Thomas Falcon <tlfalcon@linux.ibm.com>

[ Upstream commit 784688993ebac34dffe44a9f2fabbe126ebfd4db ]

VNIC protocol version is reported in big-endian format, but it
is not byteswapped before logging. Fix that, and remove version
comparison as only one protocol version exists at this time.

Signed-off-by: Thomas Falcon <tlfalcon@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/net/ethernet/ibm/ibmvnic.c | 8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/drivers/net/ethernet/ibm/ibmvnic.c b/drivers/net/ethernet/ibm/ibmvnic.c
index 897a87ae8655..20f7ab4aa2f1 100644
--- a/drivers/net/ethernet/ibm/ibmvnic.c
+++ b/drivers/net/ethernet/ibm/ibmvnic.c
@@ -3362,12 +3362,10 @@ static void ibmvnic_handle_crq(union ibmvnic_crq *crq,
 			dev_err(dev, "Error %ld in VERSION_EXCHG_RSP\n", rc);
 			break;
 		}
-		dev_info(dev, "Partner protocol version is %d\n",
-			 crq->version_exchange_rsp.version);
-		if (be16_to_cpu(crq->version_exchange_rsp.version) <
-		    ibmvnic_version)
-			ibmvnic_version =
+		ibmvnic_version =
 			    be16_to_cpu(crq->version_exchange_rsp.version);
+		dev_info(dev, "Partner protocol version is %d\n",
+			 ibmvnic_version);
 		send_cap_queries(adapter);
 		break;
 	case QUERY_CAPABILITY_RSP:
-- 
2.25.1

[PATCH AUTOSEL 4.9 6/6] l2tp: do not use inet_hash()/inet_unhash()

[Sasha Levin]

From: Eric Dumazet <edumazet@google.com>

[ Upstream commit 02c71b144c811bcdd865e0a1226d0407d11357e8 ]

syzbot recently found a way to crash the kernel [1]

Issue here is that inet_hash() & inet_unhash() are currently
only meant to be used by TCP & DCCP, since only these protocols
provide the needed hashinfo pointer.

L2TP uses a single list (instead of a hash table)

This old bug became an issue after commit 610236587600
("bpf: Add new cgroup attach type to enable sock modifications")
since after this commit, sk_common_release() can be called
while the L2TP socket is still considered 'hashed'.

general protection fault, probably for non-canonical address 0xdffffc0000000001: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f]
CPU: 0 PID: 7063 Comm: syz-executor654 Not tainted 5.7.0-rc6-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:inet_unhash+0x11f/0x770 net/ipv4/inet_hashtables.c:600
Code: 03 0f b6 04 02 84 c0 74 08 3c 03 0f 8e dd 04 00 00 48 8d 7d 08 44 8b 73 08 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 55 05 00 00 48 8d 7d 14 4c 8b 6d 08 48 b8 00 00
RSP: 0018:ffffc90001777d30 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: ffff88809a6df940 RCX: ffffffff8697c242
RDX: 0000000000000001 RSI: ffffffff8697c251 RDI: 0000000000000008
RBP: 0000000000000000 R08: ffff88809f3ae1c0 R09: fffffbfff1514cc1
R10: ffffffff8a8a6607 R11: fffffbfff1514cc0 R12: ffff88809a6df9b0
R13: 0000000000000007 R14: 0000000000000000 R15: ffffffff873a4d00
FS:  0000000001d2b880(0000) GS:ffff8880ae600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000006cd090 CR3: 000000009403a000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 sk_common_release+0xba/0x370 net/core/sock.c:3210
 inet_create net/ipv4/af_inet.c:390 [inline]
 inet_create+0x966/0xe00 net/ipv4/af_inet.c:248
 __sock_create+0x3cb/0x730 net/socket.c:1428
 sock_create net/socket.c:1479 [inline]
 __sys_socket+0xef/0x200 net/socket.c:1521
 __do_sys_socket net/socket.c:1530 [inline]
 __se_sys_socket net/socket.c:1528 [inline]
 __x64_sys_socket+0x6f/0xb0 net/socket.c:1528
 do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:295
 entry_SYSCALL_64_after_hwframe+0x49/0xb3
RIP: 0033:0x441e29
Code: e8 fc b3 02 00 48 83 c4 18 c3 0f 1f 80 00 00 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 eb 08 fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007ffdce184148 EFLAGS: 00000246 ORIG_RAX: 0000000000000029
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000441e29
RDX: 0000000000000073 RSI: 0000000000000002 RDI: 0000000000000002
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000402c30 R14: 0000000000000000 R15: 0000000000000000
Modules linked in:
---[ end trace 23b6578228ce553e ]---
RIP: 0010:inet_unhash+0x11f/0x770 net/ipv4/inet_hashtables.c:600
Code: 03 0f b6 04 02 84 c0 74 08 3c 03 0f 8e dd 04 00 00 48 8d 7d 08 44 8b 73 08 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 55 05 00 00 48 8d 7d 14 4c 8b 6d 08 48 b8 00 00
RSP: 0018:ffffc90001777d30 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: ffff88809a6df940 RCX: ffffffff8697c242
RDX: 0000000000000001 RSI: ffffffff8697c251 RDI: 0000000000000008
RBP: 0000000000000000 R08: ffff88809f3ae1c0 R09: fffffbfff1514cc1
R10: ffffffff8a8a6607 R11: fffffbfff1514cc0 R12: ffff88809a6df9b0
R13: 0000000000000007 R14: 0000000000000000 R15: ffffffff873a4d00
FS:  0000000001d2b880(0000) GS:ffff8880ae600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000006cd090 CR3: 000000009403a000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400

Fixes: 0d76751fad77 ("l2tp: Add L2TPv3 IP encapsulation (no UDP) support")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: James Chapman <jchapman@katalix.com>
Cc: Andrii Nakryiko <andriin@fb.com>
Reported-by: syzbot+3610d489778b57cc8031@syzkaller.appspotmail.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 net/l2tp/l2tp_ip.c  | 29 ++++++++++++++++++++++-------
 net/l2tp/l2tp_ip6.c | 30 ++++++++++++++++++++++--------
 2 files changed, 44 insertions(+), 15 deletions(-)

diff --git a/net/l2tp/l2tp_ip.c b/net/l2tp/l2tp_ip.c
index 4a88c4eb2301..3817c3554641 100644
--- a/net/l2tp/l2tp_ip.c
+++ b/net/l2tp/l2tp_ip.c
@@ -24,7 +24,6 @@
 #include <net/icmp.h>
 #include <net/udp.h>
 #include <net/inet_common.h>
-#include <net/inet_hashtables.h>
 #include <net/tcp_states.h>
 #include <net/protocol.h>
 #include <net/xfrm.h>
@@ -208,15 +207,31 @@ static int l2tp_ip_recv(struct sk_buff *skb)
 	return 0;
 }
 
-static int l2tp_ip_open(struct sock *sk)
+static int l2tp_ip_hash(struct sock *sk)
 {
-	/* Prevent autobind. We don't have ports. */
-	inet_sk(sk)->inet_num = IPPROTO_L2TP;
+	if (sk_unhashed(sk)) {
+		write_lock_bh(&l2tp_ip_lock);
+		sk_add_node(sk, &l2tp_ip_table);
+		write_unlock_bh(&l2tp_ip_lock);
+	}
+	return 0;
+}
 
+static void l2tp_ip_unhash(struct sock *sk)
+{
+	if (sk_unhashed(sk))
+		return;
 	write_lock_bh(&l2tp_ip_lock);
-	sk_add_node(sk, &l2tp_ip_table);
+	sk_del_node_init(sk);
 	write_unlock_bh(&l2tp_ip_lock);
+}
+
+static int l2tp_ip_open(struct sock *sk)
+{
+	/* Prevent autobind. We don't have ports. */
+	inet_sk(sk)->inet_num = IPPROTO_L2TP;
 
+	l2tp_ip_hash(sk);
 	return 0;
 }
 
@@ -598,8 +613,8 @@ static struct proto l2tp_ip_prot = {
 	.sendmsg	   = l2tp_ip_sendmsg,
 	.recvmsg	   = l2tp_ip_recvmsg,
 	.backlog_rcv	   = l2tp_ip_backlog_recv,
-	.hash		   = inet_hash,
-	.unhash		   = inet_unhash,
+	.hash		   = l2tp_ip_hash,
+	.unhash		   = l2tp_ip_unhash,
 	.obj_size	   = sizeof(struct l2tp_ip_sock),
 #ifdef CONFIG_COMPAT
 	.compat_setsockopt = compat_ip_setsockopt,
diff --git a/net/l2tp/l2tp_ip6.c b/net/l2tp/l2tp_ip6.c
index 28274f397c55..76ef758db112 100644
--- a/net/l2tp/l2tp_ip6.c
+++ b/net/l2tp/l2tp_ip6.c
@@ -24,8 +24,6 @@
 #include <net/icmp.h>
 #include <net/udp.h>
 #include <net/inet_common.h>
-#include <net/inet_hashtables.h>
-#include <net/inet6_hashtables.h>
 #include <net/tcp_states.h>
 #include <net/protocol.h>
 #include <net/xfrm.h>
@@ -221,15 +219,31 @@ static int l2tp_ip6_recv(struct sk_buff *skb)
 	return 0;
 }
 
-static int l2tp_ip6_open(struct sock *sk)
+static int l2tp_ip6_hash(struct sock *sk)
 {
-	/* Prevent autobind. We don't have ports. */
-	inet_sk(sk)->inet_num = IPPROTO_L2TP;
+	if (sk_unhashed(sk)) {
+		write_lock_bh(&l2tp_ip6_lock);
+		sk_add_node(sk, &l2tp_ip6_table);
+		write_unlock_bh(&l2tp_ip6_lock);
+	}
+	return 0;
+}
 
+static void l2tp_ip6_unhash(struct sock *sk)
+{
+	if (sk_unhashed(sk))
+		return;
 	write_lock_bh(&l2tp_ip6_lock);
-	sk_add_node(sk, &l2tp_ip6_table);
+	sk_del_node_init(sk);
 	write_unlock_bh(&l2tp_ip6_lock);
+}
+
+static int l2tp_ip6_open(struct sock *sk)
+{
+	/* Prevent autobind. We don't have ports. */
+	inet_sk(sk)->inet_num = IPPROTO_L2TP;
 
+	l2tp_ip6_hash(sk);
 	return 0;
 }
 
@@ -732,8 +746,8 @@ static struct proto l2tp_ip6_prot = {
 	.sendmsg	   = l2tp_ip6_sendmsg,
 	.recvmsg	   = l2tp_ip6_recvmsg,
 	.backlog_rcv	   = l2tp_ip6_backlog_recv,
-	.hash		   = inet6_hash,
-	.unhash		   = inet_unhash,
+	.hash		   = l2tp_ip6_hash,
+	.unhash		   = l2tp_ip6_unhash,
 	.obj_size	   = sizeof(struct l2tp_ip6_sock),
 #ifdef CONFIG_COMPAT
 	.compat_setsockopt = compat_ipv6_setsockopt,
-- 
2.25.1